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arXiv · 2406.03705

Coherent control of a triangular exchange-only spin qubit

Edwin Acuna·Joseph D. Broz·Kaushal Shyamsundar·Antonio B. Mei·Colin P. Feeney·Valerie Smetanka·Tiffany Davis·Kangmu Lee·Maxwell D. Choi·Brydon Boyd·June Suh·Wonill D. Ha·Cameron Jennings·Andrew S. Pan·Daniel S. Sanchez·Matthew D. Reed·Jason R. Petta
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Abstract

We demonstrate coherent control of a three-electron exchange-only spin qubit with the quantum dots arranged in a close-packed triangular geometry. The device is tuned to confine one electron in each quantum dot, as evidenced by pairwise charge stability diagrams. Time-domain control of the exchange coupling is demonstrated and qubit performance is characterized using blind randomized benchmarking, with an average single-qubit gate fidelity F = 99.84%. The compact triangular device geometry can be readily scaled to larger two-dimensional quantum dot arrays with high connectivity.

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Edwin Acuna, Joseph D. Broz, Kaushal Shyamsundar, Antonio B. Mei, Colin P. Feeney, Valerie Smetanka, Tiffany Davis, Kangmu Lee, Maxwell D. Choi, Brydon Boyd, June Suh, Wonill D. Ha, Cameron Jennings, Andrew S. Pan, Daniel S. Sanchez, Matthew D. Reed, Jason R. Petta. 2024-06-06. Coherent control of a triangular exchange-only spin qubit. https://doi.org/10.1103/physrevapplied.22.044057

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